Mount remote folders using SSHFS

If you want to mount remote folders and you have SSH access to the remote machine, you might want to use SSHFS. In Debian you can install the package with  apt-get install sshfs Depending on your system you might have to activate the kernel module: modprobe fuse   Supposing that the below server and folders […]


XEN installation on CentOS 5.2

  OS installation: While installation the OS, in Anaconda you just have to choose "Virtualization". All relevant XEN packages and the corresponding kernel will then be installed automatically.   Installing XEN manually: You can install the packages by executing as root: yum install xen-kernel xen Before using XEN, you have to reboot to boot the new […]


Testing STARTTLS using stunnel

You can test starttls by using this command: stunnel -D 7 -n smtp -f -c -r ip_oder_name_des_mailservers:25   Here are the options in detail: D 7 increase/Decrease the debug level – the higher the value, the more information. n smtp which protocol to use, in this case smtp f means that the process will run in foreground c […]


Creating screenshots with kwebdesktop on Linux

There are not a lot of ways automating the creation of screenshots from a linux console. One is using kwebdesktop. First of all we need to install the needed packages:   On a Debian Etch you can do this by executing: apt-get install vncserver kdesktop xfonts-base xfonts-100dpi xfonts-75dpi xfonts-intl-european xfonts-scalable xfonts-terminus xfonts-terminus-dos   In Debian […]


Secure SSH access via hosts.deny

You can use the two files /etc/hosts.allow and /etc/hosts.deny to control the ssh access to your linux box in a very simple way – without restarting services, etc. You just start your line using ALL: (really block all requests) or ALL EXCEPT (block all requests except these). Here we're blocking everything from IP 123.123.123.123 from the network range 124.124.124.0/24 and […]


Using a content filter in Postfix using Spamassassin

This is a simple way of creating a content filter in Postfix using Spamassassin. You need to have Postfix running and the following packages installed for this tutorial to work: apt-get install spamassassin spamc After the installation you have to edit /etc/default/spamassassin and change the parameter ENABLED=1 in order to make spamassassin start correctly, then: /etc/init.d/spamassassin restart   Then we […]


Finding files and directories with find

The tool find is integrated in every current linux distribution normally, so no need to install. Here are some helpful commands for daily usage: find /home -name "test.txt" -type f Find all files (-type f) named test.txt below /home   find /home -name "testdir" -type d Find all folders (-type d) named testdir below /home.   find /home -name […]


Manipulating images using Imagemagick’s convert

The package Imagemagick is coming with the command line tool /usr/bin/convert. You can install the package with: apt-get install imagemagick (Debian) emerge imagemagick (Gentoo) yum install imagemagick (CentOS, Fedora, RedHat) Convert allows you to convert image types, resize images, create thumbnails, etc.   Taking a jpg and creating a thumbnail from it: convert -thumbnail 120 […]


Map Virtualbox Guest Ports to Host

If you just would like to map a guest port from your virtual machine to your physical host, you can do it the following way (supposing that your virtual machine's name is vbox01 and we're mapping the SSH port 22 from your virtual machine to port 2222 on your physical host): VBoxManage startvm "VBOX01" -type vrdp […]


Configure a network bridge in virtualbox

That's how you can quickly create a network bridge for your Virtualbox, given your physical Virtualbox host is running on Debian: 1. Install the needed packages: apt-get install bridge-utils   2. Add the bridge to your network configuration in /etc/network/interfaces: auto br0 iface br0 inet dhcp bridge_ports eth0   3. Jetzt das Netzwerk neu starten mit […]